JP4083019B2 - Electric machine - Google Patents

Description

[0001]
The invention relates to an alternator for an electric machine, in particular a motor vehicle, of the type described in the superordinate conception of claim 1.
[0002]
According to US Pat. No. 5,907,203, alternators for motor vehicles are known. In this alternator, the voltage regulator is electrically connected to the slip ring device. The alternator has a cooling passage that extends through the voltage regulator. The voltage regulator has a casing, a printed circuit board, and a regulator chip, and the regulator chip is assembled on a fixed plate. In this case, the fixed plate of the regulator is directly adjacent to the cooling air passage path. The cooling air passage is formed by a spacer member, and the spacer member keeps the fixed plate spaced from the alternator casing. In this configuration, the printed circuit board regulator chip, that is attached to the additional securing plate is a disadvantage. Heat transfer to the sucked cooling air is limited by a fixed plate (which has a regulator chip assembled to it). The cooling air flow is not in direct contact with the printed circuit board or regulator chip. Spacer elements also form a larger structural space. This structural space adversely affects the size of the generator. Also, the manufacturing cost becomes more expensive based on the additional material cost and assembly cost.
[0003]
The object of the present invention is to provide an electric machine, in particular an alternator, with improved cooling of the regulator.
[0004]
According to the invention, this problem has been improved by the arrangement described in the characterizing part of claim 1. The core of the present invention is that the chip support is at least partially circulated by the cooling air flow, that is, the cooling air flow is at least partially flowing around the chip support. In accordance with another embodiment of the present invention, it has been found advantageous to place the chip support at a location where the cooling air flow velocity is particularly high. This is because heat conduction is very good at this point.
[0005]
In the following, the present invention will be described in detail with reference to advantageous embodiments shown in the drawings.
[0006]
Figure 1 is a cross-sectional view of an alternator having a click Roporu type rotor,
Figure 2 is a slip ring bearing shield and the alternator regulator enlarged partial view of that shown in FIG. 1,
Figure 3 shows another configuration of the cross section view corresponding to FIG. 2,
4 is a cross-sectional view of an embodiment according to the present invention corresponding to FIG.
[0007]
The configuration of the alternator will be described below with reference to FIGS. Electromechanical, in here alternator 1 for vehicles, in die-cast casing within 2 consisting of two casing halves 3,4, which is rotatably supported about a rotational axis 5, with the shaft 7 A claw pole type rotor 6 is provided. A belt wheel 10 for driving the rotor 6 is fixedly attached to the end of the rotor shaft 7 outside the casing half 4 by a nut 11. A slip ring device 12 is provided at the other end of the rotor shaft 7. The slip ring device 12 has a slip ring on the rotor shaft 7. This slip ring cooperates with the carbon brush in a known manner. In this case, the casing half 4 is configured as a bearing shield for the drive-side ball bearing 8, and the ball bearing 8 has a function as a fixed bearing. The casing half 3 is configured as a slip ring bearing shield 25 for the ball bearing 9 on the slip ring side, in which case the ball bearing 9 is smaller and is configured as a movable bearing. The two casing halves 3 and 4 are connected to each other by screws 13 to fix a central stator laminated core 14 which, in a known manner, generates a three-phase current. For this purpose, three layers of stator windings 15 are received. The rotor shaft 7 has a rotor winding 17 in the central region of the magnetic conducting ring core 16, and the rotor winding 17 corresponds to an excitation winding. A claw pole plate 18 is fixed on the rotor shaft 7 at a position directly adjacent to the front and rear of the ring core 16 and the rotor winding 17 in the axial direction. The claw pole fingers 19 of the claw pole plate 18 mesh with each other with a gap therebetween to generate an alternating magnetic field. One fan wheel 20 is assembled to the rotor shaft 7 on the outer end face side of the claw pole plate 18, and this fan wheel 20 is formed in the casing half 3 based on the rotation of the rotor shaft. Ambient air is sucked in the axial direction through a slit (not shown), and the front side of the winding head 23 on the slip ring side of the stator winding 15 is held in the radial direction and discharged to the outside. Similarly, the fan wheel 20 arranged on the drive side end face side of the claw pole plate 15 sucks the ambient air in the axial direction through a slit (not shown) formed in the casing half 4. Ambient air is blown out through the discharge opening, in front of the winding head in front of the stator winding 15. Thereby, the alternator 1 is air-cooled. The rotor winding 17 is supplied with current by the slip ring device 12, and each slip ring of the slip ring device 12 is electrically connected to one end of the rotor winding 17. A slip ring bearing shield 25 is arranged at a small interval on the side of the fan wheel 20 on the slip ring side opposite to the claw pole plate 18. Inside the slip ring bearing shield 25, the fan blade 27 An adjuster 28 is incorporated in the notch 26 in the area. The adjuster 28 adjusts the direct current flowing through the rotor winding 17 in accordance with the requirements of the automobile electrical system.
[0008]
The regulator 28 has a chip support 30 having a square cross section in the regulator casing 29. The chip support 30 is directly fixed to the chip support 30 and has a square cross section. It has a smaller regulator chip 31 of. Fixing of the regulator chip 31 is performed by selectively bonding or soldering. The chip support 30 of the regulator 28 is surrounded by a lateral thermal insulator 33. The regulator casing 29 is closed by a protective cap 34. A plug constituting unit 35 having a connecting portion 36 is arranged on the outer end face side of the casing half 3 in the adjuster casing 29.
[0009]
In the alternator 1, the tip support 30 is disposed in the notch 26 of the slip ring bearing shield 25. In this case, the tip support 30 is attached to the slip ring bearing shield 25 by a plastic layer that forms a thermal insulator 33. Relatedly thermally insulated. Heating of the regulator chip 31 by the slip ring bearing shield 25 is avoided by this thermal insulator 33. The lower side 21 of the chip support 30 facing the slip ring fan wheel 20 protrudes slightly from the notch 26 and enters the inner chamber of the alternator 1. A separate suction opening 37 for the cooling air flow 22 is arranged in the slip ring bearing shield 25 between the tip support 30 mounted in the notch 26 and the fan shaft 7.
[0010]
The cooling air flow 22 is sucked by the fan ring 20 on the slip ring side through the suction opening 37 and then blown inside along the slip ring bearing shield 25 toward the discharge opening 24 to cool the regulator chip 31. Is called. In this case, the cooling air stream 22 passes through the lower side 21 of the chip support 30 heated by the regulator chip 31. For this purpose, the chip support 30 is made of a material that conducts heat well. Based on the thermal insulator 33, it is avoided that the regulator 28 is heated strongly by the component temperature of the slip ring bearing shield 25. The lower side 21 of the chip support 30 is positioned directly on the fan blade 27. This is because, in the fan blade 27, a very high flow rate and thus a high heat transfer coefficient of the cooling air stream 22 is obtained. Here, the exhaust heat is released particularly well, so that efficient cooling of the regulator 28 is obtained. This alternator 1 is used for use with high ambient temperatures.
[0011]
Cooling of the regulator 28 is possible without a separate cooling body based on its arrangement, which results in a very inexpensive regulator 28. In order to further increase the cooling efficiency, the chip support 30 can additionally be provided with cooling fins to increase the surface area. Furthermore, the regulator chip 31 is fixed to a lead frame or current rail that extends directly into the cooling air stream 22. From this relationship, the lead frame is a current rail that is connected to each other from the beginning by the frame. The cooling of the regulator chip 31 is further improved based on this arrangement.
[0012]
Hereinafter, it will be explained in another configuration with reference to FIG. The same parts are denoted by the same reference numerals as those in FIGS. 1 and 2 , and the above description is referred to for the description of the same parts. Members that are structurally different but functionally the same are represented by the same reference with a dash.
[0013]
In this configuration , the adjuster 28 is fixed at a position away from the slip ring bearing shield 25 ′ by two spacer holders 38, and the fixing is also performed by two or more spacer holders 38 . and it is different from that of FIG. The tip support 30 of the regulator 28 is located in front of the suction opening 37 ′ in the region of the fan wheel blade 27, ie outside the casing half 3. The cooling air stream 22 ′ is sucked by the slip ring side fan wheel 20 through the suction opening 37 ′ and then blown out radially through the discharge opening 24. The notch 26 forms a suction opening 37 ′ in this configuration .
[0014]
Cooling takes place by first holding the tip support 30 and flowing before the cooling air stream 22 ′ is guided to the fan wheel 20 through the suction opening 37 ′. The exhaust heat of the chip support 30 is transmitted from the lower side 21 to the cooling air 22 ′ and can be released to the side. The surface of the chip support 30 through which the cooling air circulates is increased compared to that of the first embodiment, so that better cooling is obtained. This second embodiment is considered in particular when the cooling air stream 22 'is already strongly heated by the fan ring 20 on the slip ring side and sufficient cooling of the regulator 28 is no longer obtained. The chip support 30 is arranged at a location where the cooling air flow 22 ′ is particularly fast due to the proximity of the end face side fan wheel 20, thereby providing effective cooling.
[0015]
For real施例of the present invention will be described with reference to FIG. 4 below. Same members as those of FIG. 1 to 3 are represented by the same reference numerals, and a description thereof will be the description is referred to. Portions that are structurally different but functionally identical are represented by the same symbol with two dashes. The adjuster 28 has its tip support 30 disposed in the notch 26 in the immediate vicinity of the fan blade 27. The lower side 21 of the chip support 30 slightly enters the inner chamber of the alternator 1. On the side of the chip support 30 facing the fan shaft 7, a suction opening 37 ″ is arranged in the slip ring bearing shield 25 ″. The thermal insulator 33 "is formed along the suction opening 37" only over the partial region 39 of the side 41 of the chip support 30, thereby forming the surface 40 without the thermal insulator 33 ". ing.
[0016]
In the embodiment of the present invention, a cooling air flow 22 ″ (not shown) is sucked in the axial direction by the fan wheel 20 on the slip ring bearing side through the suction opening 37 ″ and blown out radially through the discharge opening 24. Thus, a cooling function is performed. Since the suction opening 37 ″ is positioned directly on the chip support 30, the exhaust heat of the chip support 30 is derived in the suction opening 37 ″. Further, the lower side 21 extending parallel to the fan wheel 20 is likewise circulated by the cooling air flow 22 ". The thermal insulator 33" is configured to be short at the side 41 and the cooling air flow 22 " The heat transfer is further enhanced in this region since it directly hits the chip support 30 at 40. In the embodiment of the present invention , the heat release can be caused by cooling air on the non-insulated surface 40 or the lower side 4 of the chip support 30. This is done by stream 22 ″. Again chip carrier 30, as a comparative longitudinal dimension of the cooling air flow 22 rate of "is arranged to especially high places. Alternator 1, the embodiment of the present invention the configuration shown in FIG. 2, the spacer holder The heat release is improved by the fact that the reflux surface is larger compared to the configuration shown in Fig. 1. The cooling of the regulator 28 is This is done with partially heated and unheated air in the air stream 22 ″.
[Brief description of the drawings]
1 is a cross-sectional view of an alternator having a click Roporu type rotor.
2 is an enlarged partial view of the slip ring bearing shield and the alternator regulator shown in FIG.
FIG. 3 is an enlarged partial view of a slip ring bearing shield and alternator adjuster according to the configuration shown in FIG. 1;
4 is a cross-sectional view corresponding to FIG. 3 of an embodiment according to the present invention .

Claims (4)

An electrical machine for automobiles, especially an alternator,
a) casing (2);
b) a rotor (6) rotatably supported in the casing (2) about the rotation axis (5);
c) Cooling air flow from at least one suction opening (37; 37 '; 37 ") arranged in the casing (2) to at least one discharge opening (24) arranged in the casing (2) ( 22, 22 ′, 22 ″), at least one fan (20) connected to the rotor (6),
disposed directly on the d) the chip carrier (30) has at least one regulator chip (31) for adjusting the power generation,
e) said chip carrier (30) is received in the casing (notch formed in 2) (26), and be thermally insulated from the casing (2) by a heat insulator (33) , Arranged to be at least partially circulated by the cooling air flow (22, 22 ', 22 "), and at least one suction opening (37';37") is provided in the casing (2) in the support ( 30), so that the exhaust heat of the chip support (30) is already drawn out in the suction opening (37 ″),
An electrical machine characterized by that. Chip carrier (30) is a lead frame or conductor rail, electric machine according to claim 1 Symbol placement. Electric machine according to claim 1 or 2 , wherein the chip support (30) is arranged at a location where the velocity of the cooling air flow (22, 22 ', 22 ") is particularly high. The electric machine according to any one of claims 1 to 3 , wherein the chip support (30) is made of a material having a high thermal conductivity.

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